Fluid ejection devices, such as printheads in inkjet printing systems, may use thermal resistors or piezoelectric material membranes as actuators within fluidic chambers to eject fluid drops (e.g., ink) from nozzles. In either case, fluid flows from a reservoir into the fluidic chambers through a fluid slot that extends through a substrate on which the chambers and actuators are generally formed.
With the substrate formed of silicon, however, interaction of the ink with the substrate may lead to etching of the silicon and the subsequent formation of silicate rings in the nozzles or silicate kogation on the resistors. Etching of the silicon by the ink may also lead to the formation of flaws in the substrate which may weaken the substrate and result in silicon fracture.